In this thesis, two of the earliest abhidhamma texts that are still extant today, the Pali Vibhaṅga and the Chinese Dharmaskandha, are compared and investigated. These two texts belong to the Pāli and Sarvāstivāda schools respectively, two different branches of the earlier Theravāda (Skt. Sthaviravāda) stream that developed between circa 300 B.C. and 200 A.D. They represent two divergent interpretations of the Buddha's original teachings and became incorporated into the abhidhamma collections of the two schools in question.
According to some scholars, despite sectarian differences in interpretation, commonalities also exist between these two earliest abhidhamma texts. The commonalities are likely to derive from an earlier common source, which was probably very close to the Buddha's original teaching. Therefore, comparing these two texts should provide pointers to that original teaching.
This study examines those chapters of the two texts that treat similar doctrinal topics, so that the similarities and differences between them can be identified. The commonalities thus identified will likely represent the common ancestral source of the two texts. The versions used in this study are the Pāli Text Society and Burmese editions of the Pali Vibhaṅga, and the Taisho Shinshu Daizokyo edition of the Chinese Dharmaskandha. Also consulted are the English translation of the Pāli Vibhaṅga, the commentary of the Pāli Vibhaṅga and its English translation, and the very fragmentary Sanskrit manuscript of the Dharmaskandha.
The research shows that most of the contents of the Chinese Dharmaskandha can be identified in the suttanta sections of the Pāli Vibhaṅga. The abhidhamma sections of the Pāli Vibhaṅga, with their characteristic analytical style, are largely unrepresented in the Chinese Dharmaskandha. In other words, the Dharmaskandha does not have abhidhamma sections, or it uses only a type of analysis that is close to the suttanta analysis. This analysis therefore suggests it is likely these two texts were derived from an earlier common source.